China’s state-run news agency Xinhua reports that Vice Foreign Minister Zhang Yesui criticized North Korea’s nuclear testing on Saturday, during a meeting with Pyongyang’s ambassador to China.

“The DPRK’s persisting nuclear weapon development and nuclear tests run counter to the expectations of the international community, escalate tension on the peninsula and is not conducive to the peace and stability there,” said Zhang.

“China urges the DPRK to refrain from actions that might exacerbate tension and return to the correct direction of denuclearization at an early date,” Xinhua editorialized.

The Los Angeles Times doubts Beijing will do much beyond denouncing the North Korean nuclear tests because it has “little appetite for confrontation” with its vicious client state:

“The reason North Korea dared to conduct this nuclear test is because it knew the Chinese are very much handcuffed,” said Tong Zhao, an associate at Carnegie-Tsinghua Center for Global Policy in Beijing.

China is the only lifeline for leader Kim Jong Un, whose test coincided with the anniversary of the founding of the Democratic People’s Republic of Korea by his grandfather. The bigger neighbor accounts for 90% of North Korea’s trade, much of it along the Yalu River, which serves as a border between the two countries.

Leaders worry that economic upheaval in the totalitarian nation could flood northeastern China with millions of refugees, Zhao said. But they fear much more the loss of a buffer between China and U.S.-backed South Korea, with its nearly 30,000 American troops.

Another expert, Zhang Baohui of the Center for Asian Pacific Studies at Lingnan University in Hong Kong, put it bluntly: “China has to maintain the survival of the North Korean regime. That’s its fundamental quagmire.”

Zhang added that “Chinese policy experts have rightly suggested that the Obama administration has done little with the Korean nuclear challenge,” so China has “accepted the reality of a nuclear North Korea.”